AOL acquires Time Warner | Year: 2000 | Deal size: USD 162 billion | The union created one of the largest media and entertainment conglomerates in the world. The deal, at the time, was the biggest corporate merger of all time. (Image: Reuters)

Dow Chemicals mergers with DuPont | Year: 2015 | Deal size: USD 130 billion: A definitive agreement was signed in 2015, but the merger was completed in 2017. The all-stock merger created one of the world's biggest chemicals and material firms. (Image: Reuters)

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Pfizer acquires Warner-Lambert | Year: 2000 | USD 90 billion: Following three months of defending itself from Pfizer’s hostile takeover bids, Warner-Lambert approved the merger just before 1 am. The combined entity became one of the largest drug companies in the world. (Image: Reuters)

Exxon acquires Mobil | Year: 1998 | Deal size: USD 80 billion | The two companies signed a merger agreement forming a new company — ExxonMobil, making it the largest oil firm and the third largest company in the world. It was also the largest corporate merger at that time. (Image: Reuters)

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Glaxo Wellcome acquires SmithKline Beecham | Year: 200 | Deal size: USD 75.7 billion | In January 2000, the two pharmaceutical companies announced their merger to create the world’s largest drug company and the largest company outright in the UK. (Image: Reuters)

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Comcast merges with AT&T Broadband | Year: 2001 | Deal size: USD 52 billion | It was one of the largest corporate mergers of the year. The union created the biggest cable company in the US, with 22.3 million subscribers. (Image: Reuters)

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Sanofi acquires Aventis SA | Year: 2004 | Deal size: USD 65 billion | Following an intense takeover battle that lasted months, Sanofi managed to acquire Aventis in 2004. The deal between the two French pharmaceutical companies was brokered by the French government. (Image: Reuters)